Patent GB-1042443-A (GB)
Title: Power transmission means
IPC: F16H47/04
Filed: 1965-05-05
Abstract: 1,042,443. Variable-ratio Gears. BATTELLE MEMORIAL INSTITUTE. May 5, 1965 [May 8, 1964], No. 18910/65. Heading F2C and F2D. An epicyclic gear comprises an input sun gear Rm, an output sun Rs and a reaction sun R 2  which can be connected by a clutch # 2  to a hydrostatic or other speed variator unit B which can be connected to an input shaft M by a clutch # 4  and is connected to a hydrostatic or other speed variator unit A which is selectively connectable by clutches # 1 , # 3  to an output shaft S and to a planet carrier E. As shown, the hydraulic units A, B each comprise four tiltable swash-plate pump elements hydraulically connected in parallel and symmetrically arranged around the gear axis. In operation and on starting. clutches # 1 , # 2  are engaged, unit A is set for maximum stroke and unit B to zero stroke so that the unit A is locked and the output shaft S stationed. A first, low speed range is then obtained as the stroke of unit A is reduced to zero and the stroke of unit B is increased to its maximum, unit A functioning as a motor and unit B as a pump in this range. A second speed range is obtained with the clutches # 3 , # 2  engaged and by adjusting unit A from its initial zero stroke to its maximum negative stroke position and reducing the stroke of unit B to zero, unit A functioning as a pump and unit B as a motor in this range. A third speed range is obtained with the clutches # 3 , # 4  engaged and reducing the stroke of unit A to zero and increasing the stroke of unit B to its maximum; during this speed range unit A functions as a motor and unit B as a pump. A wholly hydraulic reverse can be obtained by engaging clutches # 1 , # 4  to connect the units A, B directly to the output and input shafts. The ratio of the gear-wheels is such that with the sun gear R 2  stationed (which is the condition when changing from the first to the second speed range) the unit A is driven at the same speed by the output shaft S through the clutch # 1  and by the carrier E through the clutch # 3 , similarly the gear ratios are such that with the carrier E stationed (change-over from second to third speed range) the unit B is driven at the same speed by the input shaft M through the clutch f 4  and by the sun R 2  through the clutch # 2 . Thus, all clutch engagements are effected with the clutch parts synchronized. In order to ensure exact synchronization each clutch may be provided with a magnetic synchronizer of known type, the clutch # 1 , for example, having a sleeve 7 fast with the output shaft S and having copper studs 711 rotating opposite similar studs 13 on a flange rigid with a pinion P 1 . The clutch # 1  has a sleeve 8 shiftable axially along the output shaft S by liquid fed through ducts in the output shaft to either side of a flange 10 of the output shaft. The sleeve 8 is in permanent splined connection with the sleeve 7 and is engageable with internal splines of the pinion P 1 . The sleeve 8 engages, by way of a roller bearing 12, a sleeve 11 of the clutch # 3  so that they are moved axially simultaneously. The clutches # 2 , # 4  are similarly constructed.